1. Field of the Disclosed Embodiments
This disclosure relates to systems and methods for implementing intelligent Digital Frequency Selection (DFS) scanning using geographic location pre-screening in wireless devices.
2. Related Art
The IEEE 802.11ac (Pending) standard is a next generation wireless computer networking standard in the IEEE 802.11 series. The 802.11 ac standard is currently under development and is expected to provide standards for systems and devices that support high-throughput Wireless Local Area Networks (WLAN) in the 5 GHz band. This standard is anticipated to enable multi-station WLAN throughput of at least 1 Gigabit/sec, with improvements over IEEE 802.11n (an amendment which improves upon the previous 802.11 standards by adding multiple-input multiple-output antennas (MIMO) and operates on both the 2.4 GHz and the 5 GHz bands, approved and published in October 2009).
The 802.11ac standard is for systems and devices that will operate in the 5 GHz band only. Very High Throughput (VHT) portions of the standard will not be supported on the 2.4 GHz band. In the proposed 802.11ac standard, new channel bandwidths are added to those of the 802.11a/n standards. In the 802.11a/g standard, the channel bandwidth was specified to be only 20 MHz. In the 802.11n standard, a 40 MHz channel bandwidth option was added. The 802.11ac standard provides two additional larger channel bandwidths, 80 and 160 MHz.
An issue in using the 5 GHz band for unlicensed wireless communications is that full use of at least the wider bandwidths provided by the 802.11ac standard requires operation in the Dynamic Frequency Selection (DFS) bands of the 5 GHz band. The DFS bands are certain portions of the 5 GHz band that have stringent requirements imposed by regulatory agencies such as the Federal Communications Commission (FCC) in the United States for unlicensed devices attempting to operate in these portions of the 5 GHz band. DFS scanning is a mechanism that allows unlicensed devices to share the spectrum in the 5 GHz band with existing radar systems operating in this band, e.g., weather radars and airport radars, subject to certain conditions that are imposed to attempt to limit interference with those radar systems.